N54 Dual HPFP

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Sergeant
Jul 27, 2017
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DI is not a good choice for High HP on the N54 which is why no vendor bothers with this. The cost of two HPFPs + whatever hardware and software required to make it work is just not worth it when you can buy a PI metal intake manifold form BMS for $500 bucks.

VTT had a twin HPFP solution which no one bought because one it failures and issues left and right(like all VTT products), but also because it was expensive as fuck, $2,800 uninstalled, and needed the exact same piggy back fuel injector controller that PI requires. Oh and VTT stopped selling the twin HPFP kit because it was such a failure. That should tell you something.

Why would you want to spend $2500-$3500(got the price from above) for DI on the n54 when a $500 intake manifold does a better job? PI cleans the valves and you can use as large of injectors as you would ever want. The stock N54 injectors are a limitation, no one makes larger ones, they become an issue at high RPM when the injection window is VERY short. If you increase your redline you decrease your injection window lowering the HP the DI injectors can support.

Now, you could always overspin the HPFP for relatively small money but they make loud noises, I have been told, and often leak their precious oil etc. Not a long term solution it seems. Also they are below 700whp on 100% E85. Now on an Emix you can get closer but personally I am not a fan of E mixes at the pump.

As far as the platform being dead, it is 17 YEARS OLD. What do you expect? That being said, in 2022 a number of new products were released for the n54. Many vendors have moved on to more profitable platforms which is not surprising. The cost of a cast turbo is the same on an n54 as a s58. Guess which one you get to charge 2-3x as much for? Time to fleece the newbies! The best part is many of them are the same shitty n54 vendors.
Yes I remember this stuff. I've had my N54 since 2014. It's been alot of fun.
I held off the twin shotgun option because of all the things you mentioned above.
I've had port meth injection with twin pumps running since 2016 so I can spray as much fuel into the ports as I want.

Thing is I've always wanted something DME controlled.

I see now the reflex thing is out now that might be worthwhile.

The thing is in reality direct injection is far superior to port injection. The octane rating of direct injected methanol is 180. Direct injected ethanol is rated at 160 octane. Probably cooling and spray pattern related. Volume may be an issue.
Its a shame nobody has a way of doing it on the N54
 
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martymil

Major General
Sep 6, 2017
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Nothing wrong with high hp di only, been running it for years.

Yes seen a few brackets fail on double barrel on other cars but then again its not needed anymore with the tuning
advancements we have available today.

A single PFS overdrive is enough to give you enough hp to blow any stock n54 in no time as they are a weak motor from factory.

Yes the pumps won't last long when overdriven, roughly around 15k miles at best but that's what FCP euro warranty is for.

From what I learned running and building n54's they will be ok at 20psi on the street but won't last long at the track.

Pi has its own issues along side di, so until we get full di delete from mhd I wouldn't bother running pi myself for daily duties.

We have it running on our single turbo 135i but its not cheap like people are saying to do properly and running right.
 

GabeLo732

New Member
Apr 26, 2023
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DI is not a good choice for High HP on the N54 which is why no vendor bothers with this. The cost of two HPFPs + whatever hardware and software required to make it work is just not worth it when you can buy a PI metal intake manifold form BMS for $500 bucks.

VTT had a twin HPFP solution which no one bought because one it failures and issues left and right(like all VTT products), but also because it was expensive as fuck, $2,800 uninstalled, and needed the exact same piggy back fuel injector controller that PI requires. Oh and VTT stopped selling the twin HPFP kit because it was such a failure. That should tell you something.

Why would you want to spend $2500-$3500(got the price from above) for DI on the n54 when a $500 intake manifold does a better job? PI cleans the valves and you can use as large of injectors as you would ever want. The stock N54 injectors are a limitation, no one makes larger ones, they become an issue at high RPM when the injection window is VERY short. If you increase your redline you decrease your injection window lowering the HP the DI injectors can support.

Now, you could always overspin the HPFP for relatively small money but they make loud noises, I have been told, and often leak their precious oil etc. Not a long term solution it seems. Also they are below 700whp on 100% E85. Now on an Emix you can get closer but personally I am not a fan of E mixes at the pump.

As far as the platform being dead, it is 17 YEARS OLD. What do you expect? That being said, in 2022 a number of new products were released for the n54. Many vendors have moved on to more profitable platforms which is not surprising. The cost of a cast turbo is the same on an n54 as a s58. Guess which one you get to charge 2-3x as much for? Time to fleece the newbies! The best part is many of them are the same shitty n54 vendors.
I appreciate the info but I'm not really a newbie. I've been lurking for a few years and know most of this.

DI is better in performance, but like you said the development is bad, actually nonexistent. For a cost and development standpoint I wouldn't hesitate to do something like a DI delete and run full time PI. Or a swap. I was thinking about a 700-800whp setup with just DI and an upgraded HPFP so that's why I came to this thread hoping for updates.
The stock N54 injectors are a limitation, no one makes larger ones, they become an issue at high RPM when the injection window is VERY short. If you increase your redline you decrease your injection window lowering the HP the DI injectors can support.
I thought only the HPFP was the main limiting factor, interesting. There was an old thread stating that the injectors were capable of 1200whp according to Continental. I would imagine a higher than stock RPM would do that but keeping it stock redline might be fine. Nah, they are index injectors after all lol.
As far as the platform being dead, it is 17 YEARS OLD. What do you expect?
More development if it weren't for the injector costs. There are other platforms older than this that are doing very well but they don't really compare (K Series, etc.). The cost of injectors destroyed the platform. Maybe if a DI delete kit came out sooner it wouldn't be as dead.
The cost of a cast turbo is the same on an n54 as a s58. Guess which one you get to charge 2-3x as much for?

I don't know if I understand your question, but all the B58/S58/S55 6266 turbo kits from DOC Race are mostly the same price as the N54's.
 

GabeLo732

New Member
Apr 26, 2023
3
1
0
Its been dead for quite awhile, still some new development here and there but when you can get a b58 and throw a few grand in and make more power than the n54 will ever handle, no wonder.
With the new gen B58 yeah, not really with the old gen but I know what you mean. N54 injectors and all other bs reliability stuff cost money and a headache.
 
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